I did a fresh install of ubuntu 12.04 over my earlier 11.10.I saved the sources.list from my previous installation to another partition and replaced the sources.list in /etc/apt/ of the current installation with it,after editing it for the new distro.I got a lot of errors while using update manager so I deleted the sources.list.

At the same time,I was installing a lot of packages from synaptic manager and I left the download and install for the night(my Internet connection speed is just 256Kbps). Now,I cant find any of those packages like chromium,wine and javacc installed on my computer!Even in synaptic the packages are shown as not installed.Please help me out,I cant start another download and wait for 6 hours.

Have a look in /etc/var/cache/archives . Possibly the packages are there. But you have downloaded the packages for wrong version (11.10) if you used old source files without correct modification. You can just try to install the software. Its possible you have to re download few packages or all packages. Give a try.

thanks a lot.i deleted the sources.list before downloading softwares from synatpic.yes,all the packages i downloaded are there in /etc/var/cache/archives.wonder how i could install the downloaded packages using synaptic,rather than taking up one by one each
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scienceaurorMay 8 '12 at 9:09

First add the correct sources (using add-apt-repository <REPOSITORY LINE>), then do sudo apt-get update. Then try to install from synaptic. synaptic will pick up from the existing packages automatically. If the file got changed in server, it will be re downloaded. But I guess it will be very minimal.
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Web-EMay 8 '12 at 9:13

yes.i checked again all the packages i needed and finally it installed without downloading.thankyou very much
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scienceaurorMay 8 '12 at 9:19